Sorry to hear that's happening. If it's just their parents being an issue, your family, your brother and his girlfriend can always try to go NC but it'll be really tough. I suggest that if this has been an ongoing thing, perhaps you can try the r/raisedbynarcissists subreddit, as you may find that you're not the only one which has to deal with parents like those (however, it might be a bit different for you, but there are other subs linked to that one) I'm sure the people there will give you very very good advice, as I've never been in your situation before.